@area17/a17-lazyload
v0.1.7
Published
A simple, tiny, no dependency, lazy loader - by A17
Downloads
51
Keywords
Readme
A17 Lazy Load
Introduction
A straight forward lazy loader using IntersectionObserver
if available and if not, it uses a requestAnimationFrame
loop if available. If neither are available it does nothing.
When a watched element is in the view port it swaps data-src/data-srcset
on img
, source
and iframe
to src/srcset
. It also adds a load listener and removes the data-
attribute on load to allow you to hook styles up to the two different states.
If data-srcset
to srcset
and typeof picturefill
, attempts to run picturefill()
on the element.
When it runs out of elements to watch, the loop ends.
More detailed instructions on usage are at: https://area17.github.io/lazyload/
Usage
<script src="path/to/a17-lazyload.min.js"></script>
<script>
lazyload();
</script>
Also available via NPM:
npm install @area17/a17-lazyload
import lazyload from '@area17/a17-lazyload';
lazyload();
Issues/Contributing/Discussion
If you find a bug in a17-lazyload, please add it to the issue tracker or fork it, fix it and submit a pull request for it (👍).
The development script is dist/a17-lazyload.js
. Tabs are 2 spaces, functions are commented, variables are camel case and its preferred that its easier to read than outright file size being the smallest possible.
Make sure to include a minified version inside of dist
by running: npm run minify
(you'll need to npm run install
to install terser
). The minified version is added to the git repository for users who aren't using build tools.
Support
IE10+ because of the use of requestAnimationFrame
if no IntersectionObserver
.
Coming soon
- Work in check for
loading="lazy"
support: https://addyosmani.com/blog/lazy-loading/ - Use a
MutationObserver
to check for dynamically added elements to check.
Filesize
- ~8kb uncompressed
- ~3kb minified
- ~1kb minified and gzipped